A8 TIMING BELT REPLACEMENT PROCEDURE - …

1 1997 AUDI A8 V8 TIMING belt REPLACEMENT PROCEDURE Copyright 2003, D. Banning A8 TIMING belt REPLACEMENT PROCEDURE Parts (for a 1997 US Spec A8 Quattro): 077109119E TIMING belt 1 ea. 077109246B TIMING belt Damper 1 ea. N 905 428 01 Harmonic Balancer Bolt 1 ea. 077109244A Idler pulley 2 ea. 077109243A Tensioner pulley 1 ea. 077903137Q Serpentine belt 1 ea. 078121113F Thermostat 1 ea. 077121004H Water Pump 1 ea. 078121043A Water pump gasket 1 ea. G001200 (Red) Pentosin coolant 4-5 liters 4D0807300 Body Pin 1 ea. 026103085D Camshaft cover oil seals 2 ea.! 054115147B Front main crank seal 1 ea. OPTIONAL! Various silicone sealants and Locktite products. Tools: (All tools are metric unless otherwise specified.) Set of open-end wrenches (10mm, 12mm, and 13mm are most commonly used) Set of socket-drive allen wrenches (4mm, 5mm, and 6mm are most commonly used) Set of deep-well 3/8 drive socket wrenches (10mm, 12mm, and 13mm are most commonly used) Set of normal depth 3/8 drive socket wrenches (10mm, 12mm, and 13mm are most commonly used) Set of normal depth 1/2 drive socket wrenches (10mm, 12mm, and 13mm are most commonly used) Set of deep-well 3/8 drive socket wrenches (10mm, 12mm, and 13mm are most commonly used) Set of socket drive Torx bits, #30 most commonly used Screwdrivers, both slotted and Phillips drive, various sizes and lengths 3/8 and drive socket wrenches, fine ratchet on the 3/8 drive helps a lot SPECIAL TOOLS.

2 AS4394 Camshaft sprocket holding tool 3197 Harmonic balancer pulley holder 3341 Camshaft Locating fixtures 2079 Harmonic balancer pulley wrench NOMENCLATURE: When a position is referred to Right Side , this means the passenger side of the vehicle. Left side is therefore the driver s side of the vehicle (Left-hand drive models!!) PROCEDURE : NOTE: Whenever a part is removed from the engine, all corresponding attachment hardware should be kept with it for easy reinstallation. Clean all parts before installing back onto the engine. 1. Remove the air intake breather tubes (2) from the front of the engine compartment to the air box. The cover at the front of the engine is clipped in place- simply lift it straight up and it will come free. 2. Remove the air duct that runs from the air box to the throttle body. Loosen the two hose clamps (one on each end) and carefully loosen the rubber from the attach points.

3 3. Remove the three plastic engine beauty covers. Start with the two outer pieces (held in place with two allen head bolts each). Then remove the center cover (held in place by four allen head bolts). After removal of the covers, you should see this (replace the oil filler cap so junk doesn t fall in!): 4. Remove the noise insulation panel under the engine (large plastic cover). Then drain the radiator by opening the overflow reservoir and: a. Place a bucket under the car that can hold 3 gallons b. Connect a short length of tubing to the radiator drain (see photo) c. Remove the oval-shaped bumper cover from the driver s side front bumper (pry out with small flat-blade screwdriver- the slot for the screwdriver is towards the center of the car) d. Open the two high-point bleed ports at the driver s side rear of the engine compartment.

4 E. Disconnect the auxiliary water circulation pump electrical connector. f. Open the blue stopcock several turns and drain the radiator. If you are changing the radiator fluid at the same time, then remove the two lower (engine mounted) drain plugs. g. Use low-pressure air to blow out the radiator through the overflow canister s fill port. 5. Once the radiator has been drained, remove the two water hoses from the front of the engine. a. Remove the plastic bracket attached to the passenger side TIMING belt cover that holds the two hoses in place. b. On the upper hose, loosen the hose clamps and CAREFULLY break the hose free from its mounting points. The upper hose is connected to the engine in two places and the radiator in one place. Completely remove this hose. c. After the removal of the upper hose, a second hose becomes visible.

5 Loosen the hose clamp on this hose where it attaches to the engine and carefully remove from the engine. Simply swing this hose out of the way to the passenger side of the engine- no need to disconnect at the other end. 6. Remove the two cooling fans: a. Remove the two bolts holding the passenger side fan shroud onto the radiator. b. Using a 10mm wrench on one of the three fan pulley bolts to hold the fan still, loosen the large nut holding the fan onto the pulley (big Crescent works great). NOTE- THIS IS LEFT-HAND THREADED- DO NOT TURN TO THE LEFT TO LOOSEN!!!!! DAMAGE MAY RESULT! c. Once completely loosened, remove the fan and shroud as an assembly by lifting straight up. (The lower portion of the shroud is held in place by clips that are disengaged by lifting the shroud straight up.) d. The electric fan removal is a little trickier.

6 First, remove the body pin holding the fan in place- it is located on the fan shroud towards the center of the engine and lower (it would appear at 8:00 if you look at the fan from the front of the car). Use a long flat-blade screwdriver to break the pin- there is no way to remove without breaking it. See photo- Once the pin has been removed, the electric fan and shroud can be removed as a single unit by carefully lifting up on the small tab located at the 3:00 position (viewed from front of car) on the fan shroud and rotating the entire assembly clockwise (viewed from front of car- the top of the fan shroud moves towards the driver s side of the car) approximately 5 degrees. Then the assembly can be pulled out of the radiator shroud towards the back of the engine. Several zip-tie electrical cable tie downs must be removed in order to set the fan assembly off to the driver s side of the engine compartment.

7 These are reusable, and can be loosened by pressing down on a small tab while pushing on the end of the tie. 7. Using a permanent marker, mark the serpentine belt s direction of rotation (I use clockwise for consistency) so that it can be reinstalled in the same orientation. Remove the serpentine belt by pulling up on the tensioner stud (counter clockwise rotation viewed from the front of the engine) using a 13mm deep socket and 3/8 drive, with the drive handle towards the center of the engine. By pulling up on the tensioner, it should loosen the belt , and you should be able to easily remove the belt from the myriad pullies it involves. In the photo below, the serpentine belt has been removed in order to see the tensioner bolt. 8. Remove the fan pulley from the front of the passenger side TIMING belt cover by removing the three bolts holding it to the bearing assembly.

8 9. Remove the driver s side TIMING belt cover by removing the two large hex-head shoulder nuts from the face of the cover. You may need to gently tap the cover with a rubber mallet to loosen it for removal. 10. Using special tools 3197 and 2079, loosen (do NOT remove yet) the large bolt at the center of the harmonic balancer. The engine must be rotated such that the holding tool engages the harmonic balancer AND fits in the grooves in the passenger side TIMING belt cover casting (see the photo below). Use a drive breaker bar with the special tool to loosen this VERY tight bolt. Loosen approximately 1 turn until it loosens. 11. Remove the left and right rear cam covers- located at the rear of each cylinder head. a. Remove the driver s side camshaft position sensor cover using a 6mm hex wrench. An electrical connector bracket is removed with the assembly.

9 B. Remove the position sensor (1 bolt in center). Under the position sensor is another cover that needs to be removed- remove that cover too (2 bolts on outside radius). c. Remove the passenger side camshaft cover (there are two on the passenger side- the one you need to remove is the outboard/lower one). d. Using WD-40 as a solvent, thoroughly clean the cam covers by removing the flat o-ring seals and removing all contamination and varnish from the face and groove of the cover. A brass brush may be needed to remove the varnish. Replace the seals with new 026103085D seals and place the covers in a clean bag. e. Using WD-40 on a rag, clean the face of the heads where the cam covers mate. Remove all varnish/contamination from the flat mating surfaces. Inspect with a mirror to be sure the area is VERY clean. (This is where almost all A8s leak oil- it is very important to clean these surfaces and install new seals to prevent/stop oil leaks.)

10 12. Rotate engine to 0 Top Dead Center (TDC) using special tool 3197. 13. Install the two cam holding fixtures (3341) on the back side of the engine. If they don t fit, rotate engine one revolution back to TDC and try to reinstall the 3341s. The engine crankshaft may need to be jiggled slightly for the tools to engage, but NOT MUCH. NOTE- The deeper of the two 3341 holding fixtures goes on the driver s side camshaft, the shallower one on the passenger side. WARINING Make SURE BOTH cam tools are both fully engaged and held in place with at least two bolts apiece before proceeding!!! 14. Remove the bolt holding the front engine damper (torque damper) to the right front TIMING belt cover. 15. Remove the 5 bolts and one flanged nut holding the right side TIMING belt cover onto the engine. MAKE SURE TO NOTE WHERE THE LONG AND SHORT BOLTS GO.